Aspects of the invention relates to condensate recovery systems and methods for recovering condensate from a steam plant. Further systems and methods relate to monitoring steam loss in such a condensate recovery system, and in particular certain embodiments may be implemented for optimising the scheduling of a steam trap maintenance survey.
It is well known to provide a steam plant for generating and distributing useful energy, in the form of steam, to the point-of-use in various industrial applications.
In many systems, condensate is typically drained from the lowest points of the main plant pipeline through one or more drain-lines. In order to limit steam loss from the plant, each drain line is provided with a respective steam trap, which ideally operates to drain condensate whilst at the same time preventing the escape of “live” steam.
Whilst the presence of condensate in the main plant pipeline is undesirable, the hot condensate will nevertheless contain useful energy and therefore in a typical steam plant the drain-lines and steam traps will form part of a larger condensate recovery system designed to drain condensate (but ideally not live steam) from the main plant and to recycle the drained condensate through a down-stream boiler for subsequent use in the plant. Thus, each drain-line will typically feed into a condensate return line that in turn feeds one or more down-stream receiver tanks The receiver tanks act as temporary storage units for drained condensate, which is then typically pumped from the receiver tank into the feed-tank of a downstream boiler as required.
Efficient operation of the steam plant and condensate recovery system relies upon effective operation of the steam traps, and therefore the checking and maintenance of steam traps is very important. Conventionally, a detailed manual maintenance survey of steam traps will be carried out to identify faulty steam traps, possibly as part of a larger system audit. Current practice is to carry out such steam trap surveys periodically. However, a steam trap survey is normally a rigorous, tedious and often time-consuming process, and therefore surveys are only typically carried out at periodic intervals of six to twelve months; thus, in a worst case scenario it might be six months or more before a faulty steam trap is properly diagnosed in a maintenance survey.
Given the large number of traps associated with a steam plant, significant numbers of traps could in principle become faulty in the intervening period between maintenance surveys.